In northern coastal old growth forests a canopy develops
from tall trees screening out light to the branches below. In the deep quiet
forest the underlying branches have died off from reduced sunlight. Perhaps the
upward growth of the trees to gain height is a result of natural selection for
fastest upward mobility in competition of rival spruce, hemlock and
fir. Cedar trees stop growing somewhere south around Kupreanov Island. They are
excellent at low dense ground covering starts resembling bushes competing with
themselves choking out other species. There may be an exception to the
prevalent conifer tree rule that tree trunks become bare of branches in old
growth forests.
Some mature northern coastal fir trees develop a dense
covering of tiny branches on the trunk. While larger, primary branches have
gone through their cycle of growing large to later die off and rot away as new
branches grow higher up leaving the large tree trunk bare, there is still a
little light reaching through the treetops and the dense branches. That bare
trunk is wasted space so far as photon collecting goes. It is a metaphor for
human use of urban environment and prevalent downsizing of Earth-ecosphere
An evolutionary adaptation of tall firs in rain forests is
to exploit all that dead space devoid of photon collecting needles (conifer
equiv of leaves) and grow a covering of tiny branches with needles. Fir
trees-maybe in a homonym of fur may have tree trunks covered with a
dense growth of small branches growing directly out of the trunk. Many firs
don't have that. I don't recall observing that and many locations in S.E.
Alaska.
I have no idea if the fur-like covering of very small
branches dense with fir needles absorbing light reaching through the trees
input their chemical energy from photosynthesis directly into the upward growth
of the tree or if they are local, independent tiny trees just growing out of
the trunk's bark in the annual wetness.
I will post a picture of a fir about 75 years old with a
dense trunk cover of tiny branches. I haven't seen that kind of growth on
cedar, hemlock or spruce. On the left is the fur-covered fir tree and on the
right is a bare trunk of a usual tree and that emerged into more light after
logging. In unlogged areas with 75-year old second growth approximately) the
phenomena is common. One wonders if the trait is genetically isolated or if
cedar, hemlock and spruce trees could be made to develop that trunk covering to
increase photon collection for photosynthesis.
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